spreadsheet
worksheet
(Or rarely "worksheet") A type of
application program which manipulates numerical and string
data in rows and columns of cells. The value in a cell can be
calculated from a formula which can involve other cells. A
value is recalculated automatically whenever a value on which
it depends changes. Different cells may be displayed with
different formats.
Some spreadsheet support three-dimensional matrices and cyclic
references which lead to iterative calculation.
An essential feature of a spreadsheet is the copy function
(often using drag-and-drop). A rectangular area may be
copied to another which is a multiple of its size. References
between cells may be either absolute or relative in either
their horizontal or vertical index. All copies of an absolute
reference will refer to the same row, column or cell whereas a
relative reference refers to a cell with a given offset from
the current cell.
Many spreadsheets have a "What-if" feature. The user gives
desired end conditions and assigns several input cells to be
automatically varied. An area of the spreadsheet is assigned
to show the result of various combinations of input values.
Spreadsheets usually incorporate a macro language, which
enables third-party writing of worksheet applications for
commercial purposes.
In the 1970s, a screen editor based calculation program
called Visi-Calc was introduced. It was probably the first
commercial spreadsheet program. Soon Lotus Development
Corporation released the more sophisticated Lotus 1-2-3.
Clones appeared, (for example VP-Planner from Paperback
Software with CGA graphics, Quattro from Borland) but
Lotus maintained its position with world-wide marketing and
support - and lawyers! For example, Borland was forced to
abandon its Lotus-like pop-up menu.
While still developing 1-2-3, Lotus introduced Symphony,
which had simultaneously active windows for the spreadsheet,
graphs and a word processor.
Microsoft produced MultiPlan for the Macintosh, which
was followed by Excel for Macintosh, long before Microsoft
Windows was developed.
When Microsoft Windows arrived Lotus was still producing the
text-based 1-2-3 and Symphony. Meanwhile, Microsoft
launched its Excel spreadsheet with interactive graphics,
graphic charcters, mouse support and cut-and-paste to and
from other Windows applications. To compete with Windows
spreadsheets, Lotus launched its Allways add-on for 1-2-3 -
a post-processor that produced Windows-quality graphic
characters on screen and printer. The release of Lotus 1-2-3
for Windows was late, slow and buggy.
Today, Microsoft, Lotus, Borland and many other companies offer
Windows-based spreadsheet programs.
The main end-users of spreadsheets are business and science.
Spreadsheets are an example of a non-algorithmic programming
language.
[Dates?]
(1995-03-28)
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